Laser system for pellet-shaped articles

ABSTRACT

A pellet-shaped article inspection unit is structured for use with a conveyer mechanism having a plurality of carrier bars, each carrier bar being structured to convey a plurality of pellet-shaped articles along a predetermined path. The article inspection unit includes a first camera unit positioned adjacent a first side of the conveyer mechanism. The first camera unit is configured to sense a first predetermined characteristic, e.g., laser holes, of the plurality of pellet-shaped articles. A removal mechanism, downstream from the first camera unit, is structured to remove or maintain at least a selected one of the plurality of pellet-shaped articles from at least a selected one of the plurality of carrier bars depending on whether the first predetermined characteristic is sensed by the first camera unit. A laser unit may be provided to create unique holes in the pellet-shaped articles, e.g., those by a larger exposed surface to improve time-release characteristics of the pellet-shaped articles.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication Ser. No. 60/425,738, filed Nov. 13, 2002, and U.S.Provisional Patent Application Ser. No. 60/493,769, filed Aug. 11, 2003,the entire contents of which are herein incorporated by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

(Not Applicable)

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention also relates to processing of pellet-shapedarticles, for example, pharmaceuticals such as caplets and tablets. Inparticular, the present invention relates to drilling holes, e.g., usinga laser system, into coated pharmaceutical tablets or caplets, thedrilled holes providing for mechanical time-release of medicine withinthe articles once ingested into the digestive track, e.g. the stomach orintestines.

The present invention also relates to inspecting the laser drilled holesagainst a standard and actively accepting or rejecting selected ones ofthe pellet-shaped articles that are properly drilled.

2. Background of the Invention

Inspection units for pellet-shaped articles are known in the art. Theinspection units are typically configured to inspect and removepellet-shaped articles from a conveyer mechanism that have beenimproperly processed in a previous processing operation. Previousprocessing operations may include marking the pellet-shaped articleswith indicia, coloring the pellet-shaped articles, laser drilling holesin the pellet-shaped articles, and coating the pellet-shaped articles.These processing operations are typically completed upstream from theinspection unit such that the inspection unit may inspect if theseprocesses have been properly completed.

For example, a variety of known devices have been developed for applyinga gel coating to pellet-shaped articles. Typically, the pellet-shapedarticles, e.g., tablets, capsules, caplets and pills, are coated byhaving one side of the pellet-shaped article coated at a time. Often,due to a processing error, one or both sides of the pellet-shapedarticle are not coated at all; e.g., one side of the pellet-shapedarticle is coated twice. As a result, the pellet-shaped article has atleast one side that is not properly coated with gel. It is important forthe manufacturer to carefully inspect the pellet-shaped articles fordefects, such as an improperly coated side of the article, before thepellet-shaped article is distributed to the consumer so as to ensure thequality of the product and hence protect the safety of the consumer.

An example of an inspection unit is shown in U.S. Pat. No. 5,085,510(the '510 patent). The '510 patent discloses an inspection unit fordetecting laser drilled holes in tablets. As shown in FIG. 1, individualtablet carriers 6 are provided that transport individual tablets 2 in avertical position past two sets of cameras 12. The cameras 12 areoriented horizontally and analyze opposing sides of the tablets 2 basedon predetermined selection criteria. The cameras 12 signal a separationmeans 24 to divert preselected tablets 2. One significant limitation ofthe above unit is that only one tablet can be analyzed by a set ofcameras at a time. As a result, more than one set of cameras must beutilized to maximize the inspection rate. Moreover, each tablet carrier6 is only capable of transporting one tablet, which is inspected on bothsides thereof. Thus, the '510 patent suffers in that the feed rate isseverely limited because only one row of tablets is fed through theinspection unit.

U.S. Pat. No. 5,894,801 to Ackley, Jr., incorporated herein by referencein its entirety, describes a method and apparatus for conveying aplurality of pellet-shaped articles, such as pharmaceuticals. Theconveyer conveys the pharmaceuticals past one or more article modifyingdevices, such as a laser that forms in the pharmaceuticals drilled orblind bore holes that act as a mechanical time-release mechanism. Lasersare known from U.S. Pat. No. 5,376,771, incorporated herein by referencein its entirety.

Known lasers create the time-release holes with a diameter in the rangeof about 400-800 micrometers, and a depth of about 450-500 micrometers.Depending on the medicine involved and the speed in which the medicineis to be time-released into the digestive track, the article may beprovided with a plurality of holes. Typically, the holes are drilledthrough a coating of the article, which coating makes the article easierto swallow. The coating is encapsulates the medicine or drug until it isreleased through the laser hole. The coating typically will not dissolveor will dissolve more slowly than the drug or medicine. The holes areprovided to allow the stomach and other fluids to penetrate the interiorof the articles and thereby create a sort of pumping action to transportthe medicinal portion of the article from the interior thereof into thedigestive track, e.g., the stomach or intestines, etc.

The above hole dimensions, even if there are a plurality of holes, maynot be suitable to allow a person's digestive fluids to penetrate thearticle and release the medicine in time for proper release of themedicine. Thus, the medicine may not be released along the appropriateportion of the person's digestive track, or it may not be released atall. This can result in diminished effectiveness of the medicine anddissatisfaction to the patient.

Moreover, systems such as shown in U.S. Pat. Nos. 5,433,146, 5,768,996and 5,836,243, all to Ackley, Jr. and incorporated herein by referencein their entireties, are not suited for carrying out a coordinatedseries of drilling operations on a plurality of axially spaced rows ofarticles, because a typical drilling laser system is designed to be usedwith systems in which only one row of articles is provided.

Further, current inspection systems may require significant processingtime to determine whether the processed articles are acceptable and tothen separate acceptable articles from those that are unacceptable. Forexample, inspection of the drilled holes can slow down productivity andprocessing of the articles, especially if the inspection unit is to beintegrated with other components, such as print stations, articlehandlers, etc. This is further complicated where the conveyer includes aplurality of axially spaced rows being simultaneously processed. Thelinear speed of systems with a single row of tablets makes it difficultif not impossible to reject only individual tablets. A single bad tabletor article typically causes several tablets, whether good or bad, to berejected, thereby lowering the overall batch yield.

Accordingly, a need has developed in the art to provide one or moresystems which address the concerns described above.

The present invention provides improvements over known inspection unitssuch as the ones described above.

BRIEF SUMMARY OF THE INVENTION

One aspect of the invention relates to an improved inspection unit forinspecting and removing specified pellet-shaped articles from a conveyermechanism that have been improperly processed.

Another aspect of the invention relates to an improved camera unit thatsenses pellet-shaped articles for a predetermined characteristic.

Yet another aspect of the invention relates to an improved carrier barfor transporting pellet-shaped articles along a predetermined path.

Still another aspect of the invention relates to an improved method ofinspecting pellet-shaped articles.

A further aspect is to provide a system, e.g., a laser unit, to producean improved laser drilled hole, usually in an improved pharmaceuticalproduct.

One aspect of the invention is to provide a laser system in which astandard laser can be programmed to operate in various modes. In a firstmode, for creating smaller sized holes, the laser system can providedrilled holes having a hole diameter (or an equivalent surface area ifthe hole is not circular) in the range of about 50 micrometers to about1 mm, and preferably about 400-800 micrometers. In a second mode, forcreating larger sized holes, the laser system can provide drilled holeshaving a hole diameter or surface dimension between about 1 mm and about6 mm, and preferably in the range of about 3-6 mm. The same laser can beused in the first and the second modes. Of course, more than one smallor large size hole may be provided to each article.

Another aspect is directed towards generally increasing the surface areaof the drug or medicine which is exposed to the digestive fluids. Theincreased area can be in the form of, e.g., larger diameter drilledholes, or by etching, e.g., using a laser, cutting or removing a portionof the coating away from the medicine or drug, etc.

Another aspect is to provide a laser system for pharmaceutical articlessuch as caplets and tablets in which the laser system can provide laserdrilled holes to a plurality of rows of articles as they arecontinuously conveyed along a conveyer.

One preferred embodiment of the invention is related to a pellet-shapedarticle inspection unit configured for use with a conveyer mechanism ofthe type including, e.g., a feed drum or a plurality of carrier bars.Either the feed drum is or the carrier bars are structured to convey aplurality of pellet-shaped articles along a predetermined path. Thearticle inspection unit includes a first camera unit positioned adjacenta first side of the conveyer mechanism. The first camera unit isconfigured to sense a first predetermined characteristic of theplurality of pellet-shaped articles. A removal mechanism, downstreamfrom the first camera unit, is structured to remove at least a selectedone of the plurality of pellet-shaped articles from at least a selectedportion of the conveyer mechanism depending on whether the firstpredetermined characteristic is sensed by the first camera unit.

Another preferred embodiment relates to a camera unit for sensing aplurality of pellet-shaped articles on a conveyer mechanism. The cameraunit includes, e.g., a ring light having an opening therethrough, a lensextending through the opening, and a black/white or color ⅓ CCD coupledto the lens. Of course, other lighting, lenses and CCD sizes and typescan be used.

Yet another preferred embodiment relates to a carrier bar for a conveyermechanism that conveys a plurality of pellet-shaped articles along apredetermined path past an inspection unit having at least one cameraunit and a removal mechanism. The carrier bar includes a plurality ofpockets for receiving a plurality of pellet-shaped articles. Each of thepockets has a throughhole configured to allow (1) the at least onecamera unit to view the pellet-shaped article, and (2) the removalmechanism to remove the pellet-shaped article from that pocket in thecarrier bar.

Still another preferred embodiment is related to method of inspectingpellet-shaped articles structured for use with a conveyer mechanismincluding a plurality of carrier bars, each carrier bar structured toconvey a plurality of pellet-shaped articles along a predetermined path.The method includes sensing at least one side of the plurality ofpellet-shaped articles for a predetermined characteristic and removingat least a selected one of the plurality of pellet-shaped articles fromat least a selected one of the plurality of carrier bars depending onwhether the predetermined characteristic is sensed.

Yet another aspect is to provide an inspection unit to inspect the laserdrilled holes to ensure they conform with a given standard. Theinspection unit may include a reject system to actively accept articlesmeeting or exceeding the given standard, for example, by creating aburst of pressurized air (or a vacuum) each time an article isdetermined to be acceptable, to thereby force (or draw) away the articlefrom conveyer and into an “accept” bin. Conversely, articles notconforming to the given standard are passively rejected, e.g., byallowing them to continue further along the conveyer until they areremoved from the conveyer, e.g., by gravity, and collected in a “reject”bin.

Other aspects, features, and advantages of this invention will bedescribed in or become apparent from the following detailed descriptionwhen taken in conjunction with the accompanying drawings, which are apart of this disclosure and which illustrate, by way of example,principles of this invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings facilitate an understanding of the variousembodiments of this invention. In such drawings:

FIG. 1 is a front perspective view of one preferred embodiment ofconveyer apparatus for conveying a plurality of pellet-shaped articles;

FIG. 2 is a perspective view of the conveyer apparatus shown in FIG. 1;

FIG. 3 is an enlarged perspective view of the conveyer apparatus shownin FIG. 1 to more clearly illustrate the carrier bars of the conveyerapparatus;

FIG. 4 is an enlarged perspective view of a carrier bar of the conveyerapparatus;

FIG. 5 is a cross-sectional view through a carrier bar to more clearlyillustrate the article receiving pockets thereof;

FIG. 6 is a top plan view of an alternative embodiment of the carrierbar;

FIG. 7 is a top plan view of another alternative embodiment of thecarrier bar;

FIG. 8 is an enlarged side view of a marking apparatus;

FIG. 9 is a perspective view of the conveyer apparatus shown in FIG. 1with outer housing structures removed so as to illustrate an inspectionunit;

FIG. 10 is a perspective view illustrating a tablet-shaped article;

FIG. 11 is an enlarged perspective view of a camera unit of theinspection unit shown in FIG. 9, according to an exemplary embodiment ofthe present invention;

FIG. 12 is a rear perspective view of the conveyer apparatus shown inFIG. 1 illustrating a controller and a conveyer drive mechanism;

FIG. 13 is a schematic view illustrating an inspection unit having avacuum unit, according to an embodiment of the invention;

FIG. 14 is a perspective view illustrating a caplet-shaped article;

FIG. 15 is a schematic view illustrating the association betweencomponents of the inspection unit;

FIG. 16 is a flow chart illustrating an embodiment of the inspecting andremoving process of the inspection unit;

FIG. 17 is a schematic view of an apparatus to convey pellet-shapedarticles according to an embodiment of the present invention;

FIG. 18 is a schematic view of control system for drilling and/orinspection of drilled holes in a pellet-shaped article, according to anembodiment of the present invention;

FIG. 19 is a plan view of an pellet-shaped article and drilled holeaccording to an embodiment of the present invention;

FIG. 19A is an enlarged view of the hole of FIG. 19 with the inner andouter circles indicating the tolerance range of an exemplary hole size;

FIG. 20 is a plan view of a hole drilled in accordance with anembodiment of the present invention with the inner and outer circlesindicating the tolerance range of an exemplary hole size;

FIG. 21 is a plan view of a hole drilled in accordance with anembodiment of the present invention with the inner and outer circlesindicating the tolerance range of an exemplary hole size;

FIG. 22 is a plan view of a hole drilled in accordance with anembodiment of the present invention with the inner and outer circlesindicating the tolerance range of an exemplary hole size;

FIG. 23 is a partial cut-away perspective view of a portion of aninspection unit in accordance with an embodiment of the presentinvention; and

FIG. 24 is a perspective view of a portion of the inspection unit shownin FIG. 23.

DETAILED DESCRIPTION OF THE INVENTION

Conveyor Mechanism

FIGS. 1-3 illustrate a conveyer mechanism 12 including a plurality ofcarrier bars 24 structured to convey a plurality of pellet-shapedarticles along a predetermined conveyer path. The pellet-shaped articlesmay be in the form of capsules, caplets, pills, tablets, and otherspherical, oval, cylindrical, or polygonal shapes, as well asirregularly shaped articles.

The conveyer mechanism 12 is supported upon a frame 16 having spacedlegs 17 for providing a free-standing support. The frame 16 is alsostructured to support a feed hopper 18, a marking apparatus 14 and firstand second bins 54, 56 where pellet-shaped articles are collected, aswill be further discussed. The frame 16 includes an outer housingstructure 19 that encloses a drive mechanism of the conveyer mechanism12. The frame 16 also includes an outer housing structure 21 thatencloses a first camera unit 48 (FIG. 9). A display monitor 70 extendsfrom the frame 16 and displays diagnostic information to an operator.

The feed hopper 18 is disposed over the conveyer mechanism 12 to receivea supply of pellet-shaped articles and deliver the pellet-shapedarticles onto the conveyer mechanism 12, as shown in FIGS. 1 and 2. Asthe conveyer mechanism 12 is drawn beneath the feed hopper 18, thecarrier bars 24 will become filled with pellet-shaped articles. Beforeproceeding from beneath the feed hopper 18, the carrier bars 24 and thepellet-shaped articles will encounter a brush 52 (FIGS. 1 and 2) thatrotates, e.g., in an opposite direction than the direction of transportof the pellet-shaped articles. The brush 52 operates to returnpellet-shaped articles to the feed hopper 18 that have not been receivedwithin one of a plurality of article receiving pockets 34 provided inthe carrier bars 24. The brush 52 also operates to assist in seating thepellet-shaped articles within the pockets 34 of the carrier bars 24.After the carrier bars 24 pass by the brush 52, they pass under one ormore blow-back members 58 (FIG. 2). Specifically, the blow-back members58 are provided to create a burst of air to dislodge any articles seatedwithin the pockets of the carrier bars. The ends of each blow-backmember 58 may include one or more air jets or nozzles directed towardthe pockets in the carrier bars. This feature can be helpful if theconveyer is running but is not desirable to allow articles in the hopperto be transported about the conveyer, e.g., when performing diagnostictests or cleaning the conveyer.

As best shown in FIGS. 3-5, each of the carrier bars 24 is provided withone or more article receiving pockets 34, disposed transversely alongtheir length. Each pocket 34 has a throughhole 36 that substantiallymatches the shape of the pellet-shaped article. Specifically, eachpocket 34 includes an exterior wall 38 that defines a space in which thepellet-shaped article is to be received. An article-retaining flange 40extends radially inwardly from the exterior wall, the inner peripheralsurface of the flange 40 defining the throughhole 36. The flange 40 issuitably contoured so as to conform to the exterior shape of thepellet-shaped article. In the illustrated embodiment, the pellet-shapedarticle is a tablet. Thus, the retaining flange 40 of the pocket 34holds the tablet-shaped article around the rim in a horizontal position,as shown in FIG. 5. As a result, the tablet-shaped articles within thepockets 34 are visible from an upper side of the carrier bar 24 and aninner side of the carrier bar 24 through the throughhole 36. The pockets34 and flanges 40 thereof may be suitably modified to accommodate othershapes and sizes of the pellet-shaped articles, such as caplets andpills.

The pockets 34 of the carrier bars 24 operate to receive and entrainpellet-shaped articles from the feed hopper 18 and move thepellet-shaped articles along the conveyer path. In the illustratedembodiment, each carrier bar 24 has four pockets 34. However, thecarrier bars 24 may be provided with any number of pockets 24 disposedalong their length. For example, the number of pockets 34 may be variedby simply varying the number of pockets 34 that are placed in line alongthe manufactured carrier bars 24. As shown in FIG. 6, the pockets 34 maybe staggered to achieve an even greater pocket density. Further, asshown in FIG. 7, it is possible to stagger the pockets 34 along carrierbars 24 having scalloped edges 42 to further increase pocket density andconserve space. The scalloped edges 42 of the carrier bars 24 should beoffset so that scalloped edges 42 of adjacent carrier bars 24 willcombine to define the substantially continuous conveyer surface that isneeded to effectively receive pellet-shaped articles from the feedhopper 18. Further, the pockets of one carrier bar are staggered withrespect to adjacent pockets of the adjacent carrier bar.

In the illustrated embodiment, the carrier bars 24 are constructed toconvey the pellet-shaped articles past a marking apparatus 14 formarking desired indicia onto the pellet-shaped articles. As shown inFIG. 8, the marking apparatus 14 includes a design roll 23 that formsthe indicia to be applied to the articles, and which is disposed withinan appropriate supply of ink (not shown), and a printing roll 25 whichis in contact with both the design roll 23 and the pellet-shapedarticles which are to receive the indicia, for transferring theink-laden indicia from the design roll to the articles in question. Adoctor blade 27 is positioned adjacent the printing roll 25 to removeexcess ink from the design roll 23. Further details of the markingapparatus 14 are shown in U.S. Pat. Nos. 4,528,904 and 5,655,453 to Mr.E. Michael Ackley, Jr., which is incorporated herein by reference. It iscontemplated that the marking apparatus 14 may be an ink jet.

Following the marking apparatus 14, the carrier bars 24 convey thepellet-shaped articles past the first camera unit 48. As shown in FIG.9, the first camera unit 48 forms a part of an inspection unit 10 thatinspects and removes specified pellet-shaped articles from the conveyermechanism 12. In illustrated embodiment, the inspection unit 10 includesa first camera unit 48, a second camera unit 50, a removal mechanism 46,and a controller 60, as will be further discussed. The pellet-shapedarticles that are removed are those including a defect which may haveoccurred in a previous processing operation.

The inspection unit 10 illustrated is particularly configured to removespecified tablet-shaped articles from a conveyer mechanism 12 that havebeen improperly coated with gel in a previous processing operation. FIG.10 shows a tablet 44 having a first side 45 and a second side 47. Thesides 45, 47 are typically coated -with differently colored or huedgels. The coating operation is typically completed upstream from theinspection unit 10 such that the inspection unit 10 may inspect if thisoperation has been properly completed. The inspection unit 10 can beapplied to pellet-shaped articles having the different shapes describedabove, as would be understood by one of ordinary skill in the art.

The inspection unit 10 of the present invention determines whether bothsides 45, 47 of the tablet-shaped article 44 have been properly coatedand removes specified tablet-shaped articles that have been improperlycoated from the conveyer mechanism 12.

The inspection unit 10 may be configured and utilized to perform otheranalysis. Specifically, other processing operations may precede theinspection unit 10 such as operations that mark the pellet-shapedarticles with indicia, operations that color the pellet-shaped articles,and operations that laser drill holes in the pellet-shaped articles. Forexample, the marking apparatus 14 precedes the inspection unit 10 formarking the pellet-shaped articles with desired indicia. The inspectionunit 10 may be configured to determine whether the pellet-shaped articlehas been properly marked with the desired indicia and to removespecified pellet-shaped articles that have been improperly marked fromthe conveyer mechanism 12. See U.S. Pat. No. 5,894,801 to Ackley MachineCorporation, which is incorporated herein by reference.

Further, a variety of known apparatuses have been developed for drillingholes through coated pellet-shaped articles to provide a release pathfor the active ingredient. The articles may be coated with a sugar coat,a gel coat, a film coat, an enteric coat or an insoluble coat. Anenteric coat will not dissolve in the stomach, but will in theintestines. Moreover, the articles may have a first coating on one endor side and a second coating on the other end or side to thereby releasedifferent medicines within the same article at different locationswithin the digestive track. In another alternative, the article mayinclude two types of medicine, and the holes may be created to initiallyrelease the first medicine, and then the second medicine once all of thefirst medicine has been released. In still another example, the articlemay include two or more coating layers one on top of the other. Theinspection unit 10 may be configured to determine whether thepellet-shaped article has a hole or a properly drilled hole and toremove specified pellet-shaped articles from the conveyer mechanism 12that do not have a drilled hole or that have improper drilled holes.

In the illustrated embodiment, the inspection unit 10 forms a part of asystem for marking pellet-shaped articles. Specifically, as shown inFIGS. 1-3, the marking apparatus 14 is provided that applies desiredindicia to pellet-shaped articles. However, the inspection unit 10 maybe provided as a separate system from the marking apparatus 14. Further,the inspection unit 10 may be configured to determine whether eachpellet-shaped article is properly coated and marked with the desiredindicia. Alternatively, the inspection unit 10 may be configured to onlyperform a single analysis, e.g., determine whether the pellet-shapedarticle is properly coated. In the illustrated embodiment, theinspection unit 10 is particularly configured to sense and removespecified pellet-shaped articles from a conveyer mechanism 12 that havenot been coated or that have been improperly coated.

As shown in FIG. 9, the first and second camera units 48, 50 of theinspection unit 10 are provided along the conveyer path and areconfigured to sense a predetermined characteristic of the tablet-shapedarticle 44. In the illustrated embodiment, the first camera unit 48 isconfigured to sense whether one side of the tablet-shaped article 44 hasbeen properly coated and the second camera unit 50 is configured tosense whether the other side of the tablet-shaped article 44 has beenproperly coated. Specifically, the first and second camera units 48, 50are configured to sense for the color white (the natural color of thetablet), which indicates that a side of the tablet-shaped article 44 hasnot been coated or has been improperly coated. If at least one of thefirst and second camera units 48, 50 determines that a tablet-shapedarticle 44 has not been properly coated (e.g., senses the color white),then that particular tablet-shaped article 44 will be removed by theremoval mechanism 46 from the conveyer mechanism 12. Likewise, if boththe first and second camera units 48, 50 determine that thetablet-shaped article 44 has been properly coated (e.g., neither thefirst camera unit 48 nor the second camera unit 50 sense the colorwhite), then that particular tablet-shaped article 44 is not removed bythe removal mechanism 46.

Each camera unit 48, 50 is configured to sense a plurality of pockets 34simultaneously. In the illustrated embodiment, each camera unit 48, 50is configured to sense four pockets 34. Thus, each camera unit 48, 50 isconfigured to sense the number of pockets provided in each carrier bar24. If the carrier bar has more than four pockets, i.e., 30 pockets asshown in the carrier bars of FIGS. 6 and 7, eight camera units would beneeded to sense the plurality of pockets simultaneously (one camera unitfor every four pockets). However, it is contemplated that the cameraunits may be configured to monitor any number of pockets provided ineach of the carrier bars.

The camera units 48, 50 may be configured to sense any otherpredetermined characteristic of the pellet-shaped article. For example,the camera units 48, 50 may be configured to sense a particular indiciaand/or color appearing on the pellet-shaped article. If the indiciaand/or color of the pellet-shaped article does not fall within thepredetermined range of the camera units 48, 50, then that particularpellet-shaped article will be removed by the removal mechanism 46 fromthe conveyer mechanism 12. Alternatively, if the indicia and/or color ofthe pellet-shaped article falls within the predetermined range of thecamera units 48, 50, meaning that the pellet-shaped article is properlymarked and/or colored, then that particular pellet-shaped article is notremoved by the removal mechanism 46. Each camera unit may detect that anarticle is not contained with the carrier bar or feed drum. In thatevent, it is preferable to abstain from performing any processing atthat particular location, to thereby prevent potential damage to theconveyer apparatus. For example, the laser may cause damage to thecarrier pocket or feed drum if no article is present. Where the carrierbar or feed drum has no article and the processing still takes place,the provision of throughholes in the carrier bar or feed drum willprevent damage in the vent processing, e.g., lasering, occursinadvertently.

Further, the camera units 48, 50 may be configured to sense differentcharacteristics from one another. For example, the first camera unit 48may be configured to sense indicia and to sense if the pellet-shapedarticle has been properly coated. The second camera unit 50 may beconfigured to sense only if the pellet-shaped article has been properlycoated. This configuration can help speed processing time.

As shown in FIG. 9, the first camera unit 48 is positioned transverse tothe carrier bars 24 on an upper side of the conveyer mechanism 12 tosense one side of the tablet-shaped article 44. The second camera unit50 is positioned transverse to the carrier bars 24 on an inner side ofthe conveyer mechanism 12 to sense the other side of the tablet-shapedarticle 44. As a result, both sides 45, 47 of the tablet-shaped articles44 are sensed by the first and second camera units 48, 50 as thetablet-shaped articles 44 pass thereby. The camera unit 50 is able tosense the downwardly facing side of the tablet-shaped article 44 due tothe throughholes 36 in each of the pockets 34 of the carrier bars 24.

A drum feed printer can also be used to sense the sides of an article ortablet. For example, the product can be flipped over when beingtransferred from one drum to another drum. FIGS. 9A and 9B illustratetwo embodiments of a drum feed system in accordance with the presentinvention. As shown in FIG. 9A, a drum feed system 200 includes a hopper202 containing a plurality of articles to be processed, e.g., drilled,inspected, provided with indicia, etc., on one or both sides. Articles204 from the hopper 202 have first and second sides with first andsecond predetermined characteristics that may be different from oneanother. For example, the sides may have a different color, and/or bothsides may have a coating. A first camera unit 206 is provided to sensethe first side of the article as it is carried by a first feed drum 208converging the article along a conveying path. A second feed drum 210receives the article A from the first feed drum 208 to expose the secondside of the article A to processing. A second camera unit 212 inspectsthe second side of the article. The second feed drum 210 feeds thearticle to a conveyer mechanism 214, similar to that described below inrelation to FIG. 17. The conveyer mechanism 214 may include one or moreprocessing stations 216, 218, an inspection unit 220 or camera, andsuitable reject and accept bins 222, 224 like those shown in FIG. 17.Further processing stations 226, 228 may be provided on the first andsecond feed drums 208, 210, respectively. For example, processingstations 226, 228 may provide coatings to the first and second sides ofthe article, while the processing station 216 provides indicia, e.g.,printing, and the processing station 218 drills holes for time releasepurposes.

FIG. 9B shows a feed drum system which is similar to that shown in FIG.9A, and like reference numbers have been used to indicate like parts.However, the first feed drum 208 in FIG. 9B receives the articles 204 ina manner that seats the articles generally in the correct position. Thearticles are more accurately seated in the second feed drum 210, while athird feed drum 230 serves to re-expose the first side of the articlefor inspection/processing.

In the illustrated embodiment, the camera units 48, 50 are staggeredalong the conveying path due to physical limitations on the inner sideof the conveyer mechanism 12. Specifically, as shown in FIG. 9, theconveyer mechanism 12 is in the form of a continuous chain conveyer 20disposed upon appropriately positioned sprockets 22. The chain conveyer20 is constructed and arranged to releasably mount the carrier bars 24for collecting pellet-shaped articles from the feed hopper 18 and forconveying the collected pellet-shaped articles through the inspectionunit 10. The carrier bars 24 may be releasably mounted to the chainconveyer 20 in any suitable method. For example, the chain conveyer 20may include a mounting platform that includes a quick-release pin forreleasably mounting each of the carrier bars 24, as disclosed in U.S.Pat. No. 5,630,499, which is incorporated herein by reference.

In the illustrated embodiment, the chain conveyer 20 forms the conveyerpath that progresses along an incline portion 26 extending from the feedhopper 18 to a generally horizontal portion 28 and through a decliningportion 30 where the pellet-shaped articles are discharged. However, thechain conveyer 20 may have different configurations depending on thedesired placement of the inspection unit 10 and other units such as themarking apparatus 14. A motor unit 32 is provided to operate the chainconveyer 20 in a predetermined direction. As a result of the aboveconfiguration, the positioning of the camera unit 50 is limited due tothe positioning of the sprockets 22 of the conveyer mechanism 12.Likewise, the positioning of the camera unit 48 is limited due to thepositioning of the marking apparatus 14 that is positioned upstreamtherefrom. As a result, the camera units 48, 50 sense one side of thepellet-shaped articles at a time. Alternatively, the camera units 48, 50may be aligned such that the camera units 48, 50 sense respective sidesof the pellet-shaped articles simultaneously.

As best shown in FIG. 11, each camera unit 48, 50 in this exampleincludes a ring light 62, a lens 64, and a ⅓ black/white or color CCD66. The ring light 62 of each camera unit 48, 50 has an opening 63therethrough and is configured and positioned to properly illuminate therespective side of the pellet-shaped article as it is being sensed. Thelens 64 extends through the opening 63 in the ring light 62 and iscoupled to the black/white ⅓ CCD 66. The lens 64 includes a filterconfigured to separate image data into the color components thereof. Ingeneral, light enters the lens 64 and hits the CCD 66, where it iscaptured by photo-detectors arranged in a mosaic-like pattern. A filteris provided for the lens to allow just one color or selected colors topass through. The controller 60 has electronic circuitry thatinterpolates “missing” colors for each pixel. Of course, differentlighting systems can be used, depending on the configuration of thearticle and the predetermined characteristic being sensed. For example,when inspecting for the quality and/or accuracy of the placement ofindicia, e.g., printing, the light system should preferably bepositioned so as to avoid the creation of shadows, e.g., the light beamshould be substantially normal or perpendicular to the article havingthe indicia. If the predetermined characteristic being inspected relatesto the topography or contour of the article, it may be more preferableto angle the light beam with respect to the article, so that adetectable shadow is created to indicate the pressure or absence of adefect that would require removal/acceptance of the article.

Further, each camera unit 48, 50 is mounted to a mounting bracket 72that is adjustable relative to the conveyer mechanism 12. Specifically,the mounting bracket 72 has a slide 74 that is rigidly connected to eachcamera unit 48, 50 and a mounting structure 76 that is secured to theframe 12. The slide 74 is slidably engaged within a slot provided in themounting structure 76 such that the slide 74 and hence each camera unitcan move in fore and aft directions with respect to the mountingstructure 76 and hence the conveyer mechanism 12. As a result, thecamera units 48, 50 can be adjusted with respect to the conveyermechanism 12 for optimal performance.

The camera units 48, 50 provide signals to the controller 60 (FIG. 12),which signals the removal mechanism 46 so that specified pellet-shapedarticles can be removed from the conveyer mechanism 12. Specifically, ifeither one of the camera units 48, 50 detects the predeterminedcharacteristic (e.g., the color white indicating an improperly coatedpellet-shaped article), a signal is provided to the controller 60 whichsignals the removal mechanism 46 to remove the specified pellet-shapedarticle from the conveyer mechanism 12.

If the pellet-shaped article is determined to be defective (e.g., notproperly coated), the pellet-shaped article is discharged from therespective carrier bar 24 by the removal mechanism 46 that operates incombination with the series of throughholes 46 provided in the carrierbars 24. In the illustrated embodiment, the removal mechanism 46 ispositioned on an inner side of the conveyer mechanism 12 and isappropriately timed to operation of the conveyer mechanism 12 toeffectively discharge the specified pellet-shaped articles from thepocket 34 of the carrier bar 24 as the carrier bar 24 passes thereby.

Specifically, the controller 60 is in the form of a program logiccontrol (“PLC”) as shown in FIG. 12. The PLC controls operation of theconveyer mechanism 12, inspection unit 10, and marking apparatus 14. Asis known in the art, the PLC 60 is linked with an encoder 68 thatidentifies the exact position of each pellet-shaped article along theconveyer path so that the marking apparatus 14, the camera units 48, 50,and the removal mechanism 46 are appropriately controlled to performtheir intended function.

For example, the PLC 60 receives signals from the camera units 48, 50regarding whether each pellet-shaped article includes the predeterminedcharacteristic. The PLC 60 also receives signals from the encoder 68 toassociate the position of each pellet-shaped article with the resultsfrom the camera units 48, 50. If the predetermined characteristic issensed by the either one of the camera units 48, 50, the PLC 60 sendsthe removal mechanism 46 a signal that includes positional informationfrom the encoder 68 to remove the specified pellet-shaped article fromthe carrier bar 24.

The PLC 60 may be replaced with a computer system configured to controloperation of the conveyer mechanism 12, inspection unit 10, and markingapparatus 14 in a similar manner as described above. The inspectionprocess may be implemented on a programmed general purpose computer.However, the inspection process can also be implemented on a specialpurpose computer, a programmed microprocessor or microcontroller andperipheral integrated circuit elements, an ASIC or other integratedcircuit, a digital signal processor, a hardwired electronic or logiccircuit such as a discrete element circuit, a programmable logic devicesuch as a PLD, PLA, FPGA or PAL, or the like. In general, any device,capable of implementing a finite state machine that is in turn capableof implementing the flowchart shown in FIG. 16 (as will be discussedbelow), can be used to implement the inspection process.

The removal mechanism 46 is preferably in the form of a blower.Specifically, the removal mechanism 46 includes compressor having aplurality of blower nozzles. The compressor may be separate from or partof the unit. The number of blower nozzles is equal to the number ofpockets 34 in each carrier bar 24. As a result, one or more specifiedpellet-shaped articles from each carrier bar 24 may be removed fromtheir respective pocket 34 as it passes by the removal mechanism 44 byselectively controlling the plurality of blower nozzles. If apellet-shaped article is determined to be defective, the throughhole 36in the carrier bar 24 is configured to permit a burst of compressed airfrom a blower nozzle to pass through the throughhole 36 which removesthe individual pellet-shaped article from that pocket 34 in the carrierbar 24. The removal mechanism 46 discharges the specified pellet-shapedarticle into the first bin 54 that is in the form of a reject bin forcollecting defective pellet-shaped articles. Thus, the carrier bars 24convey a plurality of pellet-shaped articles past the inspection unit 10and selected ones of these pellet-shaped articles within a selectedcarrier bar 24 can be selectively removed by the removal mechanism 46.

Alternatively, the removal mechanism 46 may be in the form of aplurality of mechanical fingers. The number of mechanical fingers isequal to the number of pockets 34 in each carrier bar 24. Similar to theabove, one or more specified pellet-shaped articles from each carrierbar 24 may be removed from their respective pocket 34 as it passes bythe mechanical fingers by selectively actuating the mechanical fingers.

Alternatively, the removal mechanism 46 may be in the form of a vacuumunit 78, as shown in FIG. 13. The vacuum unit 78 is positioned on anupper side of the conveyer mechanism 12 following the camera units 48,50. The vacuum unit 78 may be configured to draw in specifiedpellet-shaped articles from the carrier bars 24 that are determined tobe defective and collect the defective pellet-shaped articles in areject bin 54. The vacuum unit 78 and the reject bin 54 may be formed asan integral unit If the pellet-shaped articles are acceptable, they aredeposited into an accept bin 56. The vacuum unit 78 may be secured tothe frame 12 in any suitable manner.

Further, the conveyer mechanism 12 may be provided with a suitablevacuum hold down unit 13. For example, the vacuum hold down unit 13 maybe provided below the conveyer mechanism 12 as shown in FIG. 13. Thevacuum hold down unit 13 helps to maintain the articles in apredetermined position during processing of the articles along theconveyer path, especially when the articles are subject to multipleoperations requiring registration from one processing unit to the next.The vacuum hold down unit should preferably extend below thoseprocessing units on the horizontal extent of the conveyer mechanism 12.The vacuum hold down unit 13 can be integrated with the second cameraunit 50. The vacuum hold down unit 13 may draw in air via the holes inthe carrier bars or the feed drum, as shown in FIG. 9A.

In the illustrated embodiment, the camera units 48, 50 are positionedalong the horizontal portion 28 of the conveyer path. However, thecamera units 48, 50 may be positioned along the incline portion 26following the feed hopper 18 or any other position along the conveyerpath that follows the feed hopper 18 and precedes the removal mechanism46. In the illustrated embodiment, the removal mechanism 46 ispositioned along the declining portion 30. However, the removalmechanism 46 may be positioned on any portion of the conveyer path thatfollows the camera units 48, 50. Further, the removal mechanism 46 ispositioned on the inner side of the conveyer mechanism 12 when it is inthe form of a blower or mechanical fingers in order to dischargeselected pellet-shaped articles into the reject bin 54. The removalmechanism 46 is positioned on the upper side of the conveyer mechanism12 when it is in the form of a vacuum unit 78 in order to draw inselected pellet-shaped articles into the integral reject bin. Moreover,if a vacuum unit 78 is utilized and only the first camera unit 48 isutilized to sense one selected side of the pellet-shaped articles (e.g.,inspect indicia only), it is not necessary to provide throughholes 36 inthe carrier bars 24.

As mentioned above, it is contemplated that a single camera unit may beprovided to sense a predetermined characteristic of the pellet-shapedarticle. For example, a single camera unit may be provided to sense onlyone selected side of the pellet-shaped article for the predeterminedcharacteristic. The camera unit may be provided on either the inner sideof the conveyer mechanism 12 or the upper side of the conveyer mechanism12. It may be advantageous to position a single camera unit on an innerside of the conveyer mechanism 12 to make the system more compact andprovide an isolated atmosphere to enhance the sensing capability of thecamera unit. Specifically, a camera unit on an inner side of theconveyer mechanism 12 is insulated from ambient light to provide moreaccurate readings.

For example, FIG. 14 shows a pellet-shaped article in the form of acaplet 80 having a first end 82 and a second end 84. The ends 82, 84typically have different colors. Only a single camera unit is needed toread one side of the caplet 80 in order to determine if the ends 82, 84are properly colored. If the camera unit is provided on the inner sideof the conveyer mechanism 12, the carrier bars 24 must have throughholes36 in order to sense the caplet 80. If the camera unit is provided onthe upper side of the conveyer mechanism 12, the carrier bars 24 may ormay not have throughholes 36 depending on the configuration of theremoval mechanism 46. For example, throughholes 36 are needed for theblower embodiment and throughholes 36 are not needed for the vacuum unitembodiment, as discussed above. Moreover, the inspection unit 10 may beused for a three-drum printer, an example of which is described inAckley's U.S. Pat. No. 6,286,421. For example, the camera unit may bepositioned on an inner side of one of the drums with the removalmechanism at a position following the camera unit. The three-drumprinter need not spin the article, as described in the '421 patent.

As aforesaid, the marking apparatus 14 is provided along the sameconveying path as the inspection unit 10. In the illustrated embodiment,the marking apparatus 14 precedes the inspection unit 10. However, themarking apparatus 14 may follow the inspection unit 10 if the indicia isnot to be inspected, or may not be provided at all. Alternatively, theinspection unit 10 can be programmed to sense only the coating even ifthe marking apparatus 14 is provided. Further, a marking may be appliedto the pellet-shaped articles by a process other than the markingapparatus 14 (e.g., during coating). Consequently, the inspection unit14 can inspect the marking on a pellet-shaped article even if a markingapparatus 14 is not provided.

Operation of the inspection unit will now be described in greaterdetail. After the carrier bars 24 and the pellet-shaped articles passbeneath the brush 52 and the blow-back members 58, the carrier bars 24and the pellet-shaped articles encounter the marking apparatus 14 wherethe pellet-shaped articles are marked with desired indicia. As mentionedabove, the marking apparatus 14 may not be provided. Following themarking apparatus 14, the carrier bars 24 pass by the first and secondcamera units 48, 50 of the inspection unit 10. The camera units 48, 50sense respective sides of the pellet-shaped articles for thepredetermined characteristic. If a defective pellet-shaped article isdetected (e.g., not properly coated), the camera units 48, 50 provide asignal to the controller 60 which signals the removal mechanism 46. Thecontroller 60 directs the removal mechanism 46 to remove the specifiedpellet-shaped article from the carrier bar 24. Alternatively, a singlecamera unit may be provided to sense for the predeterminedcharacteristic and to signal the controller 60 which signals the removalmechanism 46 to remove the specified pellet-shaped article from thecarrier bar 24. FIG. 15 is a schematic view that illustrates theassociation between the controller 60, the first and second camera units48, 50, and the removal mechanism 46.

More specifically, referring to FIG. 16, the pellet-shaped articles aredelivered onto the conveyer mechanism 12 by the feed hopper at step S1.A marking apparatus 14 may be provided along the conveyer path. In theillustrated embodiment, the conveyer mechanism 12 passes by the markingapparatus 14 at step S2. At step S3, the carrier bars 24 of the conveyermechanism 12 pass by the first camera unit 48 that senses one side ofthe pellet-shaped article for the predetermined characteristic. If thefirst camera unit 48 detects the predetermined characteristic at stepS4, a signal is provided to the controller 60 at step S5 to remove thatindividual pellet-shaped article. The carrier bars 24 continue along theconveyer path and pass by the second camera unit 50 at step S6 thatsenses the other side of the pellet-shaped article for the predeterminedcharacteristic. If the second camera unit 50 detects the predeterminedcharacteristic at step S7, a signal is provided to the controller 60 atstep S8 to remove that individual pellet-shaped article. If at least oneof the camera units 48, 50 detects a defective pellet-shaped article, asignal is provided to the controller 60 to remove that specifiedpellet-shaped article.

After passing by the first and second camera units 48, 50, the conveyermechanism 12 will cause the pellet-shaped articles to progress to thedeclining portion 30 of the conveyer path. If the pellet-shaped articleis determined to be defective by either one of the camera units (i.e.,the controller 60 has received a signal from at least one of the firstand second camera units 48, 50) at step S9, the controller 60 signalsthe removal mechanism 46 positioned adjacent the declining portion 30 toremove the specified pellet-shaped article at step S11. Specifically,the removal mechanism 46 discharges the specified pellet-shaped articleinto the reject bin 54 where defective pellet-shaped articles arecollected. If the pellet-shaped article is not defective (i.e., thecontroller 60 has not received a signal from either of the camera units48, 50), the pellet-shaped article continues down the declining portion30 until it falls out under the influence of gravity and continues alonga path to the second bin in the form of an accept bin 56 (shown in FIGS.1 and 2) at step S11 where non-defective pellet-shaped articles arecollected. Alternatively, the non-defective pellet-shaped articles maycontinue along a path to an adjacent conveyer mechanism that transportsthe accepted or non-defective pellet-shaped articles to a furtherprocessing operation. The system may include an additional dischargemechanism to facilitate the discharge of non-defective pellet-shapedarticles from pockets of the carrier bars 24.

As indicated in FIG. 16, rejected articles are actively rejected whereasaccepted articles are passively accepted. In another embodiment, theaccepted articles can be ejected into an accept bin (active acceptance),while the rejected articles are allowed to remain in the conveyer to betransported into a reject bin (passive rejection).

FIGS. 17-24 illustrate another embodiment of the present invention. Itis to be understood that various components described below may beincluded within the embodiments described above, and various componentsdescribed above may be used in conjunction with the components describedbelow.

FIG. 17 shows a schematic view of a transporting and processingapparatus 110 according to an illustrative embodiment of the presentinvention. In one example, the transporting and processing apparatusincludes a conveyer loop 112 which is entrained about a pair ofsprockets 114A and 114B to travel along a transport path in a directionindicated by an arrow B. Other configurations are also contemplated. Adispenser 116, e.g., a hopper, is disposed over the conveyer loop 112and dispenses articles onto the conveyer loop 112. The articles can beedible or non-edible including confectioneries, non-confectioneries,candies, food, pharmaceuticals or any other discreet type articles.Several dispensers are well known in the art and may be used in thepresent invention, including but not limited to hoppers, rollers andfeed dispensers. The dispenser 116 is positioned adjacent the sprocket114A which causes the conveyer loop 112 to follow along a predeterminedradius of curvature. The conveyer loop 112 travels around a curvilinearpath made up of substantially linear sections and substantiallynon-linear sections, e.g., where the sprockets 114A and 114B arelocated.

After the dispenser 116 dispenses the articles to the conveyer loop 112,the articles are transported past one or more processing stations 118and 120. The processing stations may be drilling stations, printingstations or any other process which can be applied to modify theappearance and/or shape of the articles. The processing stations 118 or120 perform first and second processes on the articles which arecoordinated with another. For example, the first processing station 118may be a first printer and the second processing station 120 may be asecond printer that serially print component images of a composite imageon the articles in registered relationship with one another. Theprocessing stations 118 and 120 are located on a portion of the conveyerloop 112 which is substantially linear or not less than a predeterminedradius of curvature. The conveyer loop 112 transports the article pastthe sprocket 114B where the articles are inspected by an inspection unit125. Following inspection, acceptable and non-acceptable articles areseparated from one another. For example, rejected articles may bereleased into a drop-off or “reject” bin 122, while acceptable articlesmay be directed to an accept bin (123) or suitable post processingreceptacles, such as a blistered package, etc. The conveyer loop 112follows this cycle to pick up additional articles from the dispenser116. The articles may be maintained in a predetermined position, e.g.,using the system described in U.S. Pat. No. 6,314,876 to Ackley, Jr.,incorporated herein by reference in its entirety.

The above embodiment is only for the purposes of illustration, as otherconfigurations for the transport loop are within the scope of theinvention. For example, the ramp-type conveyer described in FIG. 1 caninclude the systems describe above in FIG. 17, or a drum feed systemcould be employed.

FIG. 18 is a schematic diagram showing a control system for use with aconveying apparatus as described above. A controller 130, e.g., in theform of a CPU, personal computer or a programmable logic control unit,coordinates various components of a laser control system and aninspection unit. A main drive motor 135 is operatively coupled, e.g., toone of the sprockets 114A or 114B (FIG. 17) to transport the articlesfrom station to station along the transport path. The drive motor 135 ispreferably designed to continuously drive the conveyer loop 112. Anencoder 140 is coupled to the motor 135 and provides a signal todetermine the position of the articles on the transport loop 112relative to the processing stations 118 and 120.

A laser control system 145 and a galvanometer 150 are in communicationwith the controller 130. The laser control system 145 controls a lasersuch as commercially available from Coherent, model no. Diamond K-250.The galvanometer is also commercially available from GSI Lumonics, modelno. HSM15M2. These components are provided to drill laser holes in thearticles A. However, it is to be understood that the above laser andgalvanometer are exemplary only, and that other lasers and galvanometerscan be used as well.

A vision and lighting system 155 and reject system 160 are also incommunication with the controller 130, to provide an active system toinspect articles after one or more processing operations and to activelyaccept selected ones of articles which are found to meet predeterminedrequirements programmed into or accessible to the controller 130. Thevision and light system 155 and the reject system 160 together can beconsidered to constitute an inspection unit, in one example. Thecontroller 130 may be programmed to control multiple lasers, lasercontrol systems, galvos and/or vision and reject systems.

Laser System

FIG. 19 shows one example of an article A which is round, although thearticle could be a caplet as well. The article A has a depth, diameterand shape which may vary. The article A is provided with a laser hole165, which is shown on an enlarged scale in FIG. 19A to include minimumand maximum diameters indicating the acceptable tolerance range of thehole size, as indicated by the inner and outer circles. The diameter ofthe hole 165 is designed to be in the range of about 50 micrometers toabout 1 mm, for smaller holes, and about 1 mm to about 6 mm for largerholes. The depth of the hole is typically in the range of about 450-500micrometers. The depth of the hole is at least equal to and preferablygreater than the thickness of the coating to achieve the desired effect.The depth is controlled by pulsing the laser at least one time, andpreferably multiple times in the same position until the depth isproper, as shown in FIG. 20. The diameter of the drilled hole is betweenthe minimum and maximum diameters determined by the acceptable tolerancerange of the hole size.

In a first mode, the diameter of the holes is controlled by using alaser to create relatively smaller holes having a diameter in the rangeof about 50 micrometers to about 1 mm, and preferably about 400-800micrometers. In a second mode, the same laser is controlled to create arelatively large composite hole using a series of holes in apredetermined pattern, as shown in FIGS. 21 and 22. In FIGS. 21 and 22,a relatively larger diameter hole, e.g., in the range of about 1 mm toabout 6 mm, preferably about 3-6 mm, is created by pulsing the laserwith smaller diameter holes in different positions to create the largediameter hole. In FIG. 21, the pattern includes seven holes in thegeneral shape of a hexagon, while FIG. 22 shows the pattern to includemany more smaller holes, e.g., 37 holes with 4 on each side of agenerally hexagonal shaped hole. FIGS. 21 and 22 show that the overallsize of the combined holes falls within the tolerance range for theselected hole diameter.

In general the number and size of the holes and the pattern size andshape may vary to create the desired hole diameter. Changing the holediameter and/or depth affects the surface area of the article exposed tothe fluids in the digestive tract, which may be used to better controlthe release of the medicine. In other words, one inventive conceptextends to increasing the surface-area exposed to the fluid in thestomach, regardless of how the increased surface area is achieved. Theincreased surface area may be uniform or non-uniform cross section.Increased surface area may be achieved via larger drilled holes, or byetching away a portion of the coating using the laser, for example. Theincreased surface area includes the increased surface area of the wallsof the drilled holes, due to the enlarged diameter of the hole.

The conveyer belt, galvo position, and laser are all controlled by thesame control unit. It is a multi-axis motion controller withsophisticated move profile controls. The conveyer belt has encoderfeedback to provide carrier belt position and speed information to thesystem. The galvo has two mirrors mounted to high performance servomotors. The laser pointing is controlled by the mirror positions. Themirror positions are determined by the controller.

In one aspect of the invention the galvo is commanded to point the laserat the center of the tablet and then the controller fires the laser fora set period of time. This period of time combined with the laser pulsewidth and pulse period will determine the hole depth. For example, eachproduct may be in the vicinity of the laser for a total time of about50-300 milliseconds (ms), preferably about 100-200 ms, and mostpreferably 150 ms, depending on the product involved. In that time, thepulse period may be about 400-600 microseconds, e.g., about 500microseconds, in which the product can be lasered. The pulse width maybe about 40-60 microseconds, e.g., about 50 microseconds. In that pulsewidth, the product may be pulsed 7-8 times to create the proper depth,although the correct depth may be achieved with a single pulse, or morethan 7-8 pulses.

In another aspect of the invention, the galvo will be commanded toperform a complex series of moves, while at the same time electronicallygearing to the conveyer belt. The controller will command the laser tofire at the appropriate times. The depth of the hole is determined belaser pulse width, pulse period and galvo speed. The diameter of thehole is determined by the software in the controller.

One advantage of this system is that the same laser can be used tocreate holes having a diameter from about 50 micrometers to about 1 mmfor relatively smaller holes, and, for relatively larger holes, thediameter ranges from about 1 mm to about 6 mm. This avoids the need toswitch lasers or to buy lasers with a large diameter, which would beexpensive.

The laser can also be used to drill holes on a plurality of rows ofarticles at the same time. The range of motion for the galvo is suchthat it is able to point at multiple products across the conveyer bed.For example, the laser can be fired at 6 discrete products with ⅝″spacing between the products. The galvo can be commanded to point ateach product in sequence and then fire the laser at each.

Inspection

FIG. 23 is a partial perspective view of the inside of the conveyer loop112, which in this example takes the form of a plurality of carrier bars170 having at least one row and preferably several axially spaced rows,e.g., six, of recesses 171 for receiving articles A. The carrier bars170 are coupled to a conveyer chain 172 trained about the sprockets 114Aand keyed to a common shaft 173.

A drum 175 forming a part of the reject system 160 of the inspectionunit is positioned between and rotates with the sprockets 114A about theshaft 173. The drum 175 includes a plurality of holes 176 that areprovided in an array of six rows, along the axis of the drum 175, tomatch the number of axially spaced rows in the carrier bars 170.Further, the holes in the drum 175 are spaced apart a distance, in acircumferential sense, which is about the same as the distance betweenrecesses 171 in adjacent carrier bars. In this example, the holes inboth the drum and the carrier bars are through-holes.

Provided inside the drum 175 is a solenoid pack 180 which includes oneor more solenoids 180 a-180 f, in this example, to match the number ofaxially spaced rows in the drum 175 and carrier bars 170. Each solenoidis associated with a solenoid tube 185, each tube 185 having a fitting195 coupled to a shoe 190 to which the solenoid pack 180 is mounted.Shoe 190 is better seen in FIG. 24 which for simplicity and clarity doesnot include the transport loop or sprockets, etc.

FIG. 24 shows that the shape of the shoe 190 is complimentary to theinside surface of the drum 175. Each tube 180 end includes a fitting 195which is provided to the shoe 190. Shoe 190 includes number of holes,e.g., six, corresponding to the number of axially spaced rows of thedrum 175. Shoe 190 is fixedly coupled to the frame of the conveyer suchthat the drum 175 and carrier bars rotate around the fixed shoe 190. Theposition of the shoe 190 can be changed using a bracket 200 having aslot with a pin or threaded bolt with optional spacer which can befastened to the frame.

In operation, the drum 175 rotates with the shaft as the carrier bars170 are conveyed along the transport path. As the carrier bars 170 passover the drum 175, the holes 176 of the drum 175 register with therecesses 171 of the carrier bars 170. If the articles within therecesses 171 are determined to be acceptable, then the solenoidassociated with the article in its recess 171 is activated, e.g., torelease a burst of pressurized air (from a pressurized air source) whichforces the articles away from the recesses and into an appropriatecollection bin for acceptable articles. For any articles that are notacceptable, the solenoid is not activated and the article continues torotate with the carrier bar until gravity allows the article to bereleased into a “reject” bin, e.g., bin 22 (FIG. 17).

Although it is contemplated that rejected articles, instead of acceptedarticles, can be forced out of the recesses 171, the more preferablesystem includes forcing the accepted articles away from the recesses(active acceptance/passive rejection). In particular, solenoids whichare only occasionally activated need more lead time than a solenoidwhich is continuously and repeated activated. Thus, it is thought thatthe better approach is to passively allow the rejected articles to beremoved from the conveyer, e.g., by gravity, and to actively accept theaccepted articles. Stated differently, it is easier and faster todeactivate a solenoid for a rejected article than it is to activate asolenoid for a rejected article. Further, it is also desirable topassively reject so that a failed solenoid will not cause the system tooutput failed products.

An inspection camera of the type disclosed in the embodiment of FIGS.1-16 can be used to provide a signal which can be compared to apredetermined standard, to determine whether the article is acceptableor not acceptable. The camera may be mounted outside the conveyer loopto inspect one side of the article. Alternatively or in addition, asecond camera can be mounted inside the conveyer loop, e.g., within thedrum 175. The signal from the camera can be used to determine theacceptability of a number of characteristics of the article, besides thedimensions of the drilled holes, e.g., logo placement, coating, etc.

It can thus be appreciated that the objectives of the present inventionhave been fully and effectively accomplished. The foregoing specificembodiments have been provided to illustrate the structural andfunctional principles of the present invention and are not intended tobe limiting. To the contrary, the present invention is intended toencompass all modifications, alterations, and substitutions within thespirit and scope of the present disclosure.

1-86. (canceled)
 87. A laser drilling system for pellet-shaped articlescomprising: a laser; and a controller to allow the laser to create atleast one laser drilled hole in the articles having a diameter spanninga range from about 50 micrometers to about 6 mm.
 88. The laser drillingsystem of claim 87, wherein the range is about 50 micrometers to 1 mmfor relatively large holes, and about 1 mm to about 6 mm for relativelylarger holes.
 89. A laser system for pellet-shaped articles comprising:a laser to create a laser beam; a deflector to deflect the laser beam;and a controller to allow the deflector to split the laser beam into aplurality of axially spaced rows.
 90. An apparatus for conveyingpellet-shaped articles comprising: a conveyer to transport a pluralityof articles; and a laser system according to claim
 89. 91-96. (canceled)97. The laser system according to claim 89, wherein the controller unitorients the deflector such that the laser beam impacts the article todefine a predetermined shape and pattern defined by a series ofgenerally round holes or shapes.
 98. The laser system according to claim89, wherein the laser beam depth is controlled in the range of 450-500μm.
 99. The laser system according to claim 98, wherein the depth of thepattern is equal to or greater than a thickness of a coating on thearticles.
 100. The laser system according to claim 98, wherein the laserbeam depth is controlled by pulsing the laser beam one or more times.101. The laser system according to claim 89, wherein the laser beam isconfigured to drill a hole having a diameter in the range of 50 μm toabout 6 mm.
 102. The laser system according to claim 101, wherein forholes in the range of 1 mm to 6 mm, a plurality of smaller holes arecombined to form said drilled hole.